As the first snows of winter arrive, many of the world’s most marvellous mountain roads are closed until the thaw. However, these five perfect passes in the Swiss Alps remain open all hours and ready for an Alpine adventure.

The Morgan Plus Four is a car designed for sunny drives on high days and holidays. This trip’s lofty ambition is to reach the high society hangout of St Moritz in Switzerland in the depths of winter.

We don’t normally write about train journeys at Detour, but when said railway takes you and your car to one of the best mountain passes in Switzerland we’ll make an exception.